Citations

8527 Background: Pts who have exhausted lenalidomide (LEN) and bortezomib (BORT) treatment (Tx) have a poor prognosis. A significant proportion of pts have RI with increasing incidence during disease course. POM + LoDEX has demonstrated efficacy in pts with prior LEN and BORT, including those with RI. MM-003 is an open-label, multicenter, phase 3 trial comparing POM + LoDEX vs HiDEX in RRMM pts who failed LEN and BORT and progressed on their last Tx. Methods: Pts must have failed LEN and BORT after ≥ 2 consecutive cycles of each (alone or in combination) and must have been refractory to last prior Tx (progressive disease [PD] during Tx or within 60 days). Pts with creatinine clearance (CrCl) < 45 mL/min were excluded. Randomization was 2:1 to POM 4 mg D1–21 + DEX 40 mg (20 mg for pts aged > 75 y) qw; or DEX 40 mg (20 mg for pts aged > 75 y) D1–4, 9–12, and 17–20 (28-D cycles). Tx continued until PD or unacceptable adverse event (AE). The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS) and AEs. This analysis examined pts with or without moderate RI (CrCl < 60 vs ≥ 60mL/min). Results: 302 pts received POM + LoDEX; 153 pts received HiDEX, 31% and 39% had moderate RI, respectively. Pts with moderate RI were more likely to be older (64% vs 36% aged > 65 y) vs no RI. Median follow-up was 4 mo. Median PFS and OS were significantly longer with POM + LoDEX vs HiDEX regardless of RI (Table). Similar AE rates for POM + LoDEX as well as HiDEX Tx were seen in pts with and without moderate RI (Table). Discontinuation due to AE was 5% vs 7% (no moderate RI) and 11% vs 5% (moderate RI). Conclusions: POM + LoDEX significantly extended PFS and OS vs HiDEX in pts with or without moderate RI. Tolerability of POM + LoDEX was acceptable across subgroups, with few discontinuations due to AE. Clinical trial information: NCT01311687. [Table: see text]

8510 Background: RRMM patients (pts) who have exhausted treatment (Tx) with bortezomib (BORT) and lenalidomide (LEN) or thalidomide have a poor prognosis with short overall survival (OS). HiDEX is a well-established standard Tx in RRMM. POM has demonstrated clinical efficacy in pts refractory to LEN and BORT. MM-003 compared POM + LoDEX vs. HiDEX in RRMM pts who failed LEN and BORT and who progressed on their last Tx. Methods: Pts must have been refractory to last prior Tx (progressive disease [PD] during Tx or within 60 days) and failed LEN and BORT after ≥ 2 consecutive cycles of each (alone or in combination). Pts were randomized 2:1 to receive 28-day cycles of POM 4 mg D1–21 + DEX 40 mg (20 mg for pts aged > 75 y) weekly or DEX 40 mg (20 mg for pts aged > 75 y) D1–4, 9–12, and 17–20. Tx continued until PD or unacceptable toxicity. The primary endpoint was progression-free survival (PFS). Secondary endpoints included OS, overall response rate (ORR; ≥ partial response), and safety. Analyses were based on intent to treat. Results: 455 pts were randomized to POM + LoDEX (n = 302) or HiDEX (n = 153). The median number of prior Tx was 5 (range 1-17). 72% were refractory to LEN and BORT. Median follow-up was 4 months. POM + LoDEX significantly extended median PFS (3.6 vs. 1.8 months, HR = 0.45, P < .001) and OS (not reached vs. 7.8 months, HR = 0.53, P < .001) vs. HiDEX. The OS benefit was observed despite 29% of HiDEX pts receiving POM after PD. The trial met the primary endpoint of PFS, crossed the upper boundary for OS superiority, and the Data Monitoring Committee recommended crossover from HiDEX to POM ± DEX. With updated data, the ORR was 21% for POM + LoDEX vs. 3% for HiDEX (P < .001) and 24% vs 3% for pts randomized ≥ 6 months post-enrollment (P < .001). The most frequent grade 3/4 adverse events (AEs) for POM + LoDEX vs. HiDEX were neutropenia (42% vs. 15%), anemia (27% vs. 29%), and infection (24% vs. 23%). Discontinuation due to AEs was infrequent (7% vs. 6%). Updated data will be presented. Conclusions: POM + LoDEX significantly extended PFS and OS vs. HiDEX in pts who failed LEN and BORT. POM + LoDEX should become a standard of care in RRMM pts who have exhausted Tx with LEN and BORT. Clinical trial information: NCT01311687.

Abstract Background The purpose of this study was to estimate precise age-specific tubo-ovarian carcinoma (TOC) and breast cancer (BC) risks for carriers of pathogenic variants in RAD51C and RAD51D. Methods We analyzed data from 6178 families, 125 with pathogenic variants in RAD51C, and 6690 families, 60 with pathogenic variants in RAD51D. TOC and BC relative and cumulative risks were estimated using complex segregation analysis to model the cancer inheritance patterns in families while adjusting for the mode of ascertainment of each family. All statistical tests were two-sided. Results Pathogenic variants in both RAD51C and RAD51D were associated with TOC (RAD51C: relative risk [RR] = 7.55, 95% confidence interval [CI] = 5.60 to 10.19; P = 5 × 10-40; RAD51D: RR = 7.60, 95% CI = 5.61 to 10.30; P = 5 × 10-39) and BC (RAD51C: RR = 1.99, 95% CI = 1.39 to 2.85; P = 1.55 × 10-4; RAD51D: RR = 1.83, 95% CI = 1.24 to 2.72; P = .002). For both RAD51C and RAD51D, there was a suggestion that the TOC relative risks increased with age until around age 60 years and decreased thereafter. The estimated cumulative risks of developing TOC to age 80 years were 11% (95% CI = 6% to 21%) for RAD51C and 13% (95% CI = 7% to 23%) for RAD51D pathogenic variant carriers. The estimated cumulative risks of developing BC to 80 years were 21% (95% CI = 15% to 29%) for RAD51C and 20% (95% CI = 14% to 28%) for RAD51D pathogenic variant carriers. Both TOC and BC risks for RAD51C and RAD51D pathogenic variant carriers varied by cancer family history and could be as high as 32–36% for TOC, for carriers with two first-degree relatives diagnosed with TOC, or 44–46% for BC, for carriers with two first-degree relatives diagnosed with BC. Conclusions These estimates will facilitate the genetic counseling of RAD51C and RAD51D pathogenic variant carriers and justify the incorporation of RAD51C and RAD51D into cancer risk prediction models.

Background Encapsulating peritoneal sclerosis (EPS) is a rare complication of peritoneal dialysis. The causes of EPS are not well defined and are likely multifactorial. A suitable animal model would facilitate research into the pathophysiology and treatment of EPS. Methods We developed a helper-dependent adenovirus that expresses both green fluorescent protein (GFP) and active transforming growth factor-beta (TGF-β1; HDAdTGF-β1). Mice were administered HDAdTGF-β1 via intraperitoneal injection and the response was compared with mice administered either first-generation adenovirus expressing TGF-β1 (AdTGF-β1) or control adenovirus (AdGFP). Results HDAdTGF-β1-treated mice continued to express the GFP reporter transgene to day 74, the end of the observation period. Transgene expression lasted less than 28 days in the animals treated with first-generation adenoviruses. Animals treated with first-generation AdTGF-β1 demonstrated submesothelial thickening and angiogenesis at day 7, with almost complete resolution by day 28. The HDAdTGF-β1-treated mice demonstrated progressive peritoneal fibrosis with adhesion formation and encapsulation of bowels. Weight gain was significantly reduced in animals treated with HDAdTGF-β1 compared to both the control-treated animals and the AdTGF-β1-treated animals. Inflammation was not a major component of the fibroproliferative response. Conclusions Peritoneal administration of a first-generation AdTGF-β1 leads to transient gene expression, resulting in a resolving fibrotic response and histology similar to that seen in simple peritoneal sclerosis. Prolonged TGF-β1 expression induced by the helper-dependent HDAdTGF-β1 led to changes in peritoneal morphology resembling EPS. This suggests that TGF-β1 may be a contributing factor in both simple peritoneal sclerosis and EPS. This model will be useful for elucidation of the mechanism of EPS and evaluation of potential treatment.

PURPOSE In studies of men of European ancestry, rare pathogenic variants in DNA repair pathway genes have been shown to be associated with risk of aggressive prostate cancer. The contribution of rare coding variation to prostate cancer risk in men of African ancestry has not been established. METHODS We sequenced a panel of 19 DNA repair and cancer predisposition genes in 2,453 African American and 1,151 Ugandan cases and controls with prostate cancer. Rare variants were classified as pathogenic or putatively functionally disruptive and examined in association with prostate cancer risk and disease aggressiveness in gene and pathway-level association analyses. RESULTS Pathogenic variants were found in 75 of 2,098 cases (3.6%) and 31 of 1,481 controls (2.1%; odds ratio [OR], 1.82; 95% CI, 1.19 to 2.79; P = .0044), with the association being stronger for more aggressive disease phenotypes (OR, 3.10; 95% CI, 1.54 to 6.23; P = .0022). The highest risks for aggressive disease were observed with pathogenic variants in the ATM, BRCA2, PALB2, and NBN genes, with ORs ranging from approximately 4 to 15 in the combined study sample of African American and Ugandan men. Rare, nonpathogenic, nonsynonymous variants did not have a major impact on risk of overall prostate cancer or disease aggressiveness. CONCLUSION Rare pathogenic variants in DNA repair genes have appreciable effects on risk of aggressive prostate cancer in men of African ancestry. These findings have potential implications for panel testing and risk stratification in this high-risk population.

Diffuse large B-cell lymphoma is a heterogeneous disease, commonly described by cell-of-origin (COO) molecular subtypes. We sought to identify novel patient subgroups through an unsupervised analysis of a large public dataset of gene expression profiles from newly diagnosed de novo DLBCL patients, yielding two biologically distinct subgroups characterized by differences in the tumor microenvironment. Pathway analysis and immune deconvolution algorithms identified higher B-cell content and a strong proliferative signal in subgroup A and enriched T-cell, macrophage, and immune/inflammatory signals in subgroup B, reflecting similar biology to published DLBCL stratification research. A gene expression classifier, featuring 26 gene expression scores, was derived from the public dataset to discriminate subgroup A (classifier-negative, immune-low) and subgroup B (classifier-positive, immune-high) patients. Subsequent application to an independent series of diagnostic biopsies and replicated the subgroups with immune cell composition confirmed via immunohistochemistry. Avadomide, a CRL4CRBN E3 ubiquitin ligase modulator, demonstrated clinical activity in relapsed/refractory DLBCL patients, independent of COO subtypes. Given the immunomodulatory activity of avadomide and need for a patient selection strategy, we applied the gene expression classifier to pretreatment biopsies from relapsed/refractory DLBCL patients receiving avadomide (NCT01421524). Classifier-positive patients demonstrated an enrichment in response rate and progression-free survival of 44% and 6.2 months versus 19% and 1.6 months for classifier-negative patients (HR=0.49 [0.280, 0.86]; P=.0096). The classifier was not prognostic for R-CHOP or salvage immunochemotherapy. The classifier described here discriminates DLBCL tumors based on tumor and non-tumor composition and has potential utility to enrich for clinical response to immunomodulatory agents including avadomide.

Abstract Background: Gastric cancer risk evolves over time due to environmental, dietary, and lifestyle changes including Helicobacter pylori (H. pylori) infection and consumption of hot peppers (i.e. capsaicin). H. pylori infection promotes gastric mucosal injury in the early phase of capsaicin exposure. In addition, capsaicin consumption is reported to suppress immune function and increase host susceptibility to microbial infection. This relationship suggests a need to investigate the mechanism of how both H. pylori infection and capsaicin contribute to gastric inflammation and lead to gastric cancer. No previous experimental animal models have been developed to study this dual association. Here we developed a series of mouse models that progress from chronic gastritis to gastric cancer. C57-Balb/c mice were infected with the H. pylori (SS1) strain and then fed capsaicin (0.05% or 0.2g/kg/day) or not. Consequently, we investigated the association between H. pylori infection and capsaicin consumption during the initiation of gastric inflammation and the later development of gastric cancer. Tumor size and phenotype were analyzed to determine the molecular mechanism driving the shift from gastritis to stomach cancer. Gastric carcinogenesis was also prevented in these models using the ornithine decarboxylase inhibitor DFMO (2-difluoromethylornithine). Results: This study provides evidence showing that a combination of H. pylori infection and capsaicin consumption leads to gastric carcinogenesis. The transition from chronic gastritis to gastric cancer is mediated through interleukin-6 (IL-6) stimulation with an incidence rate of 50%. However, this progression can be prevented by treating with anti-inflammatory agents. In particular, we used DFMO to prevent gastric tumorigenesis by reducing inflammation and promoting recovery of disease-free stasis. The anti-inflammatory role of DFMO highlights the injurious effect of inflammation in gastric cancer development and the need to reduce gastric inflammation for cancer prevention. Conclusions: Overall, these mouse models provide reliable systems for analyzing the molecular mechanisms and synergistic effects of H. pylori and capsaicin on human cancer etiology. Accordingly, preventive measures like reduced capsaicin consumption, H. pylori clearance, and DFMO treatment can lessen gastric cancer incidence. Lastly, anti-inflammatory agents like DFMO can play important roles in prevention of inflammation-associated gastric cancer.

Abstract Persons of African ancestry (AA) have a twofold higher risk for multiple myeloma (MM) compared with persons of European ancestry (EA). Genome-wide association studies (GWASs) support a genetic contribution to MM etiology in individuals of EA. Little is known about genetic risk factors for MM in individuals of AA. We performed a meta-analysis of 2 GWASs of MM in 1813 cases and 8871 controls and conducted an admixture mapping scan to identify risk alleles. We fine-mapped the 23 known susceptibility loci to find markers that could better capture MM risk in individuals of AA and constructed a polygenic risk score (PRS) to assess the aggregated effect of known MM risk alleles. In GWAS meta-analysis, we identified 2 suggestive novel loci located at 9p24.3 and 9p13.1 at P &lt; 1 × 10−6; however, no genome-wide significant association was noted. In admixture mapping, we observed a genome-wide significant inverse association between local AA at 2p24.1-23.1 and MM risk in AA individuals. Of the 23 known EA risk variants, 20 showed directional consistency, and 9 replicated at P &lt; .05 in AA individuals. In 8 regions, we identified markers that better capture MM risk in persons with AA. AA individuals with a PRS in the top 10% had a 1.82-fold (95% confidence interval, 1.56-2.11) increased MM risk compared with those with average risk (25%-75%). The strongest functional association was between the risk allele for variant rs56219066 at 5q15 and lower ELL2 expression (P = 5.1 × 10−12). Our study shows that common genetic variation contributes to MM risk in individuals with AA.